Opinions/Advice needed for "wandering" issue

I've got an 05 doublecab long box 4x4. At the end of last summer I installed a Ready-lift 2-1/4" spacer above the front strut assemblies and had it aligned. I have also had the rear suspension TSB done.
I like the ride and the stance of the truck but it really wanders now. Especially if I'm pulling my 2500# travel trailer. All the roads are asphalt up here in BC and most of them have a lot of heavy truck traffic so the "grooves" in the road can be quite pronounced. Before the lift the truck did not do this at all, now it's almost scary at times.
What do you think my options are:

1 - Live with the problem
2 - Remove the levelling kit and go back to stock
3 - Have another alignment done by someone else (maybe the dealer??)
4 - Install a smaller spacer for 1-1/4" of lift (Daystar)
5 - bite the bullet and buy new upper control arms that have more castor. If I go with this option does it really cure the problem??? At $500+ it'd be nice to know for sure.

I have searched this forum and found some info that is helpful but not enough to be able to make the choice with any certainty.

Cheers

 

New UCAs are whats recommended for wandering problems after a lift.

 

Check your tire pressure- make sure your tires aren't over-inflated. Where did you get the allignment done? I had mine alligned twice after I installed a lift, the first at Pepboys and the second at a dealership in conjunction with the TSB, and only the third time was done correctly (by the same dealership when I complained that the allignment was still off). Also, when you add a lift, although the camber can usually be brought within specs, they cannot usually be brought to the same specs as stock. Basically, your front tires/wheels will probably be slightly angled inward. As Da Hui mentioned, aftermarket UCAs can correct that, and I imagine increasing the castor could help too as you say.